For the Caribbean bend on the situation (and because you asked about variations from school to school)...
If you fail a class at Ross, you repeat the whole semester and re-take the course you failed. This gets you "off track" with the rest of your starting class, but still allows you to move through the program. If you fail the repeated class, or if you fail a class more than twice, you're out. Period.
There is no summer break. The pre-clinical portion goes straight through. A significant number of people, for various reasons but mainly because of their own doing, simply cannot make it through the program. A lot of people who started in my class are either no longer a part of it, or are no longer at the school. It's like basketball try-outs: each semester you're, in effect, competing with those who "made the cut" from the previous semester. It's not a "Caribbean vacation"... trust me.
For more info, PM me.
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MS2 Ross University
Portsmouth, Dominica